<input type="button" value="按钮" onclick="ttt()">
<select id="select_90190" size=3>
<option value="">a</option>
<option value="">b</option>
<option value="">cccccccccc</option>
</select>
<script language="javascript">
<!--
function ttt(i){
if(!i){
select_90190.multiple = true;
setTimeout('ttt(1)',1);
}
for (var i=0;i<select_90190.length;i++)
{
select_90190.options[i].selected = true;
}
}//-->
</script>
<select id="select_90190" size=3>
<option value="">a</option>
<option value="">b</option>
<option value="">cccccccccc</option>
</select>
<script language="javascript">
<!--
function ttt(i){
if(!i){
select_90190.multiple = true;
setTimeout('ttt(1)',1);
}
for (var i=0;i<select_90190.length;i++)
{
select_90190.options[i].selected = true;
}
}//-->
</script>
解决方案 »
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